Android Studio Giraffe Essentials - Kotlin Edition: Developing Android Apps Using Android Studio 2022.3.1 and Kotlin

1. Introduction....28

1.1 Downloading the Code Samples....28

1.2 Feedback....28

1.3 Errata....29

2. Setting up an Android Studio Development Environment....30

2.1 System requirements....30

2.2 Downloading the Android Studio package....30

2.3 Installing Android Studio....31

2.3.1 Installation on Windows....31

2.3.2 Installation on macOS....31

2.3.3 Installation on Linux....32

2.4 The Android Studio setup wizard....32

2.5 Installing additional Android SDK packages....33

2.6 Installing the Android SDK Command-line Tools....36

2.6.1 Windows 8.1....37

2.6.2 Windows 10....38

2.6.3 Windows 11....38

2.6.4 Linux....38

2.6.5 macOS....38

2.7 Android Studio memory management....38

2.8 Updating Android Studio and the SDK....39

2.9 Summary....40

3. Creating an Example Android App in Android Studio....42

3.1 About the Project....42

3.2 Creating a New Android Project....42

3.3 Creating an Activity....43

3.4 Defining the Project and SDK Settings....43

3.5 Enabling the New Android Studio UI....44

3.6 Modifying the Example Application....45

3.7 Modifying the User Interface ....46

3.8 Reviewing the Layout and Resource Files....52

3.9 Adding Interaction....55

3.10 Summary....56

4. Creating an Android Virtual Device (AVD) in Android Studio....58

4.1 About Android Virtual Devices....58

4.2 Starting the Emulator....60

4.3 Running the Application in the AVD....61

4.4 Running on Multiple Devices....62

4.5 Stopping a Running Application....63

4.6 Supporting Dark Theme....63

4.7 Running the Emulator in a Separate Window....64

4.8 Enabling the Device Frame....67

4.9 Summary....68

5. Using and Configuring the Android Studio AVD Emulator ....70

5.1 The Emulator Environment....70

5.2 Emulator Toolbar Options....70

5.3 Working in Zoom Mode....72

5.4 Resizing the Emulator Window....72

5.5 Extended Control Options....72

5.5.1 Location....73

5.5.2 Displays....73

5.5.3 Cellular....73

5.5.4 Battery....73

5.5.5 Camera....73

5.5.6 Phone....73

5.5.7 Directional Pad....73

5.5.8 Microphone....73

5.5.9 Fingerprint....73

5.5.10 Virtual Sensors....74

5.5.11 Snapshots....74

5.5.12 Record and Playback....74

5.5.13 Google Play....74

5.5.14 Settings....74

5.5.15 Help....74

5.6 Working with Snapshots....74

5.7 Configuring Fingerprint Emulation....75

5.8 The Emulator in Tool Window Mode....77

5.9 Creating a Resizable Emulator....77

5.10 Summary....78

6. A Tour of the Android Studio User Interface....80

6.1 The Welcome Screen....80

6.2 The Menu Bar....81

6.3 The Main Window....81

6.4 The Tool Windows....83

6.5 The Tool Window Menus....86

6.6 Android Studio Keyboard Shortcuts....86

6.7 Switcher and Recent Files Navigation....87

6.8 Changing the Android Studio Theme....88

6.9 Summary....89

7. Testing Android Studio Apps on a Physical Android Device....90

7.1 An Overview of the Android Debug Bridge (ADB)....90

7.2 Enabling USB Debugging ADB on Android Devices....90

7.2.1 macOS ADB Configuration....91

7.2.2 Windows ADB Configuration....92

7.2.3 Linux adb Configuration....93

7.3 Resolving USB Connection Issues....93

7.4 Enabling Wireless Debugging on Android Devices....94

7.5 Testing the adb Connection....96

7.6 Device Mirroring....96

7.7 Summary....96

8. The Basics of the Android Studio Code Editor....98

8.1 The Android Studio Editor....98

8.2 Splitting the Editor Window....101

8.3 Code Completion....101

8.4 Statement Completion....103

8.5 Parameter Information....103

8.6 Parameter Name Hints....103

8.7 Code Generation....103

8.8 Code Folding....105

8.9 Quick Documentation Lookup....106

8.10 Code Reformatting....106

8.11 Finding Sample Code....107

8.12 Live Templates....107

8.13 Summary....108

9. An Overview of the Android Architecture....110

9.1 The Android Software Stack....110

9.2 The Linux Kernel....111

9.3 Android Runtime – ART....111

9.4 Android Libraries....111

9.4.1 CC Libraries....112

9.5 Application Framework....112

9.6 Applications....113

9.7 Summary....113

10. The Anatomy of an Android App....114

10.1 Android Activities....114

10.2 Android Fragments....114

10.3 Android Intents....115

10.4 Broadcast Intents....115

10.5 Broadcast Receivers....115

10.6 Android Services....115

10.7 Content Providers....116

10.8 The Application Manifest....116

10.9 Application Resources....116

10.10 Application Context....116

10.11 Summary....116

11. An Introduction to Kotlin....118

11.1 What is Kotlin?....118

11.2 Kotlin and Java....118

11.3 Converting from Java to Kotlin....118

11.4 Kotlin and Android Studio....119

11.5 Experimenting with Kotlin....119

11.6 Semi-colons in Kotlin....120

11.7 Summary....120

12. Kotlin Data Types, Variables, and Nullability....122

12.1 Kotlin Data Types....122

12.1.1 Integer Data Types....123

12.1.2 Floating-Point Data Types....123

12.1.3 Boolean Data Type....123

12.1.4 Character Data Type....123

12.1.5 String Data Type....123

12.1.6 Escape Sequences....124

12.2 Mutable Variables....125

12.3 Immutable Variables....125

12.4 Declaring Mutable and Immutable Variables....125

12.5 Data Types are Objects....125

12.6 Type Annotations and Type Inference....126

12.7 Nullable Type....127

12.8 The Safe Call Operator....127

12.9 Not-Null Assertion....128

12.10 Nullable Types and the let Function....128

12.11 Late Initialization (lateinit)....129

12.12 The Elvis Operator....130

12.13 Type Casting and Type Checking....130

12.14 Summary....131

13. Kotlin Operators and Expressions....132

13.1 Expression Syntax in Kotlin....132

13.2 The Basic Assignment Operator....132

13.3 Kotlin Arithmetic Operators....132

13.4 Augmented Assignment Operators....133

13.5 Increment and Decrement Operators....133

13.6 Equality Operators....134

13.7 Boolean Logical Operators....134

13.8 Range Operator....135

13.9 Bitwise Operators....135

13.9.1 Bitwise Inversion....135

13.9.2 Bitwise AND....136

13.9.3 Bitwise OR....136

13.9.4 Bitwise XOR....136

13.9.5 Bitwise Left Shift....137

13.9.6 Bitwise Right Shift....137

13.10 Summary....138

14. Kotlin Control Flow....140

14.1 Looping Control flow....140

14.1.1 The Kotlin for-in Statement....140

14.1.2 The while Loop ....141

14.1.3 The do ... while loop ....142

14.1.4 Breaking from Loops....142

14.1.5 The continue Statement ....143

14.1.6 Break and Continue Labels....143

14.2 Conditional Control Flow....144

14.2.1 Using the if Expressions ....144

14.2.2 Using if ... else Expressions ....145

14.2.3 Using if ... else if ... Expressions ....145

14.2.4 Using the when Statement....145

14.3 Summary....146

15. An Overview of Kotlin Functions and Lambdas....148

15.1 What is a Function?....148

15.2 How to Declare a Kotlin Function....148

15.3 Calling a Kotlin Function....149

15.4 Single Expression Functions....149

15.5 Local Functions....149

15.6 Handling Return Values....150

15.7 Declaring Default Function Parameters....150

15.8 Variable Number of Function Parameters ....150

15.9 Lambda Expressions....151

15.10 Higher-order Functions....152

15.11 Summary....153

16. The Basics of Object Oriented Programming in Kotlin....154

16.1 What is an Object?....154

16.2 What is a Class?....154

16.3 Declaring a Kotlin Class....154

16.4 Adding Properties to a Class....155

16.5 Defining Methods....155

16.6 Declaring and Initializing a Class Instance....155

16.7 Primary and Secondary Constructors....155

16.8 Initializer Blocks....158

16.9 Calling Methods and Accessing Properties....158

16.10 Custom Accessors....158

16.11 Nested and Inner Classes....159

16.12 Companion Objects....160

16.13 Summary....162

17. An Introduction to Kotlin Inheritance and Subclassing....164

17.1 Inheritance, Classes and Subclasses....164

17.2 Subclassing Syntax....164

17.3 A Kotlin Inheritance Example....165

17.4 Extending the Functionality of a Subclass....166

17.5 Overriding Inherited Methods....167

17.6 Adding a Custom Secondary Constructor....168

17.7 Using the SavingsAccount Class....168

17.8 Summary....168

18. An Overview of Android View Binding....170

18.1 Find View by Id....170

18.2 View Binding ....170

18.3 Converting the AndroidSample project....171

18.4 Enabling View Binding....171

18.5 Using View Binding....171

18.6 Choosing an Option....172

18.7 View Binding in the Book Examples....172

18.8 Migrating a Project to View Binding....173

18.9 Summary....173

19. Understanding Android Application and Activity Lifecycles....174

19.1 Android Applications and Resource Management....174

19.2 Android Process States....174

19.2.1 Foreground Process....175

19.2.2 Visible Process....175

19.2.3 Service Process....175

19.2.4 Background Process....175

19.2.5 Empty Process....176

19.3 Inter-Process Dependencies ....176

19.4 The Activity Lifecycle....176

19.5 The Activity Stack....176

19.6 Activity States....177

19.7 Configuration Changes....177

19.8 Handling State Change....178

19.9 Summary....178

20. Handling Android Activity State Changes....180

20.1 New vs. Old Lifecycle Techniques....180

20.2 The Activity and Fragment Classes....180

20.3 Dynamic State vs. Persistent State....182

20.4 The Android Lifecycle Methods....182

20.5 Lifetimes....184

20.6 Foldable Devices and Multi-Resume....185

20.7 Disabling Configuration Change Restarts....185

20.8 Lifecycle Method Limitations....185

20.9 Summary....186

21. Android Activity State Changes by Example....188

21.1 Creating the State Change Example Project....188

21.2 Designing the User Interface....189

21.3 Overriding the Activity Lifecycle Methods....190

21.4 Filtering the Logcat Panel....192

21.5 Running the Application....193

21.6 Experimenting with the Activity....194

21.7 Summary....195

22. Saving and Restoring the State of an Android Activity....196

22.1 Saving Dynamic State....196

22.2 Default Saving of User Interface State....196

22.3 The Bundle Class....197

22.4 Saving the State....198

22.5 Restoring the State....199

22.6 Testing the Application....199

22.7 Summary....199

23. Understanding Android Views, View Groups and Layouts....200

23.1 Designing for Different Android Devices....200

23.2 Views and View Groups....200

23.3 Android Layout Managers....200

23.4 The View Hierarchy....202

23.5 Creating User Interfaces....203

23.6 Summary....203

24. A Guide to the Android Studio Layout Editor Tool....204

24.1 Basic vs. Empty Views Activity Templates....204

24.2 The Android Studio Layout Editor....208

24.3 Design Mode....208

24.4 The Palette....209

24.5 Design Mode and Layout Views....210

24.6 Night Mode....211

24.7 Code Mode....211

24.8 Split Mode....212

24.9 Setting Attributes....213

24.10 Transforms....214

24.11 Tools Visibility Toggles....215

24.12 Converting Views....216

24.13 Displaying Sample Data....217

24.14 Creating a Custom Device Definition....218

24.15 Changing the Current Device....218

24.16 Layout Validation....219

24.17 Summary....220

25. A Guide to the Android ConstraintLayout....222

25.1 How ConstraintLayout Works....222

25.1.1 Constraints....222

25.1.2 Margins....223

25.1.3 Opposing Constraints....223

25.1.4 Constraint Bias....224

25.1.5 Chains....225

25.1.6 Chain Styles....225

25.2 Baseline Alignment....226

25.3 Configuring Widget Dimensions....226

25.4 Guideline Helper....227

25.5 Group Helper....227

25.6 Barrier Helper....227

25.7 Flow Helper....229

25.8 Ratios....230

25.9 ConstraintLayout Advantages....230

25.10 ConstraintLayout Availability....231

25.11 Summary....231

26. A Guide to Using ConstraintLayout in Android Studio....232

26.1 Design and Layout Views....232

26.2 Autoconnect Mode....234

26.3 Inference Mode....234

26.4 Manipulating Constraints Manually....234

26.5 Adding Constraints in the Inspector....236

26.6 Viewing Constraints in the Attributes Window....236

26.7 Deleting Constraints....237

26.8 Adjusting Constraint Bias....238

26.9 Understanding ConstraintLayout Margins....238

26.10 The Importance of Opposing Constraints and Bias....240

26.11 Configuring Widget Dimensions....242

26.12 Design Time Tools Positioning....243

26.13 Adding Guidelines....244

26.14 Adding Barriers....246

26.15 Adding a Group....247

26.16 Working with the Flow Helper....248

26.17 Widget Group Alignment and Distribution....248

26.18 Converting other Layouts to ConstraintLayout....250

26.19 Summary ....250

27. Working with ConstraintLayout Chains and Ratios in Android Studio....252

27.1 Creating a Chain....252

27.2 Changing the Chain Style....254

27.3 Spread Inside Chain Style....255

27.4 Packed Chain Style....255

27.5 Packed Chain Style with Bias....255

27.6 Weighted Chain....255

27.7 Working with Ratios....256

27.8 Summary....258

28. An Android Studio Layout Editor ConstraintLayout Tutorial....260

28.1 An Android Studio Layout Editor Tool Example....260

28.2 Preparing the Layout Editor Environment....260

28.3 Adding the Widgets to the User Interface....261

28.4 Adding the Constraints....264

28.5 Testing the Layout....266

28.6 Using the Layout Inspector....266

28.7 Summary....267

29. Manual XML Layout Design in Android Studio....268

29.1 Manually Creating an XML Layout....268

29.2 Manual XML vs. Visual Layout Design....271

29.3 Summary....271

30. Managing Constraints using Constraint Sets....272

30.1 Kotlin Code vs. XML Layout Files....272

30.2 Creating Views....272

30.3 View Attributes....273

30.4 Constraint Sets....273

30.4.1 Establishing Connections....273

30.4.2 Applying Constraints to a Layout....273

30.4.3 Parent Constraint Connections....273

30.4.4 Sizing Constraints....274

30.4.5 Constraint Bias....274

30.4.6 Alignment Constraints....274

30.4.7 Copying and Applying Constraint Sets....274

30.4.8 ConstraintLayout Chains....274

30.4.9 Guidelines....275

30.4.10 Removing Constraints....275

30.4.11 Scaling....275

30.4.12 Rotation....276

30.5 Summary....276

31. An Android ConstraintSet Tutorial....278

31.1 Creating the Example Project in Android Studio....278

31.2 Adding Views to an Activity....278

31.3 Setting View Attributes....279

31.4 Creating View IDs....280

31.5 Configuring the Constraint Set....281

31.6 Adding the EditText View....282

31.7 Converting Density Independent Pixels (dp) to Pixels (px)....283

31.8 Summary....284

32. A Guide to Using Apply Changes in Android Studio....286

32.1 Introducing Apply Changes....286

32.2 Understanding Apply Changes Options....286

32.3 Using Apply Changes....287

32.4 Configuring Apply Changes Fallback Settings....288

32.5 An Apply Changes Tutorial....288

32.6 Using Apply Code Changes....288

32.7 Using Apply Changes and Restart Activity....289

32.8 Using Run App....289

32.9 Summary....289

33. An Overview and Example of Android Event Handling....290

33.1 Understanding Android Events....290

33.2 Using the android:onClick Resource....290

33.3 Event Listeners and Callback Methods....291

33.4 An Event Handling Example....291

33.5 Designing the User Interface....292

33.6 The Event Listener and Callback Method....292

33.7 Consuming Events....294

33.8 Summary....295

34. Android Touch and Multi-touch Event Handling....296

34.1 Intercepting Touch Events....296

34.2 The MotionEvent Object....297

34.3 Understanding Touch Actions....297

34.4 Handling Multiple Touches....297

34.5 An Example Multi-Touch Application....298

34.6 Designing the Activity User Interface....298

34.7 Implementing the Touch Event Listener....298

34.8 Running the Example Application....301

34.9 Summary....301

35. Detecting Common Gestures Using the Android Gesture Detector Class....302

35.1 Implementing Common Gesture Detection....302

35.2 Creating an Example Gesture Detection Project....303

35.3 Implementing the Listener Class....303

35.4 Creating the GestureDetectorCompat Instance....305

35.5 Implementing the onTouchEvent() Method....305

35.6 Testing the Application....306

35.7 Summary....306

36. Implementing Custom Gesture and Pinch Recognition on Android....308

36.1 The Android Gesture Builder Application....308

36.2 The GestureOverlayView Class....308

36.3 Detecting Gestures....308

36.4 Identifying Specific Gestures....308

36.5 Installing and Running the Gesture Builder Application....308

36.6 Creating a Gestures File....309

36.7 Creating the Example Project....309

36.8 Extracting the Gestures File from the SD Card....309

36.9 Adding the Gestures File to the Project....310

36.10 Designing the User Interface....310

36.11 Loading the Gestures File....311

36.12 Registering the Event Listener....312

36.13 Implementing the onGesturePerformed Method....312

36.14 Testing the Application....313

36.15 Configuring the GestureOverlayView....313

36.16 Intercepting Gestures....314

36.17 Detecting Pinch Gestures....314

36.18 A Pinch Gesture Example Project....314

36.19 Summary....316

37. An Introduction to Android Fragments....318

37.1 What is a Fragment?....318

37.2 Creating a Fragment....318

37.3 Adding a Fragment to an Activity using the Layout XML File....319

37.4 Adding and Managing Fragments in Code....321

37.5 Handling Fragment Events....322

37.6 Implementing Fragment Communication....322

37.7 Summary ....324

38. Using Fragments in Android Studio - An Example....326

38.1 About the Example Fragment Application....326

38.2 Creating the Example Project....326

38.3 Creating the First Fragment Layout....326

38.4 Migrating a Fragment to View Binding....328

38.5 Adding the Second Fragment....329

38.6 Adding the Fragments to the Activity....330

38.7 Making the Toolbar Fragment Talk to the Activity....331

38.8 Making the Activity Talk to the Text Fragment....334

38.9 Testing the Application....335

38.10 Summary....335

39. Modern Android App Architecture with Jetpack....336

39.1 What is Android Jetpack?....336

39.2 The Old Architecture....336

39.3 Modern Android Architecture....336

39.4 The ViewModel Component....337

39.5 The LiveData Component....337

39.6 ViewModel Saved State....338

39.7 LiveData and Data Binding....338

39.8 Android Lifecycles....339

39.9 Repository Modules....339

39.10 Summary....340

40. An Android ViewModel Tutorial....342

40.1 About the Project....342

40.2 Creating the ViewModel Example Project....342

40.3 Removing Unwanted Project Elements....342

40.4 Designing the Fragment Layout....343

40.5 Implementing the View Model....344

40.6 Associating the Fragment with the View Model....345

40.7 Modifying the Fragment....346

40.8 Accessing the ViewModel Data....346

40.9 Testing the Project....347

40.10 Summary....347

41. An Android Jetpack LiveData Tutorial....348

41.1 LiveData - A Recap....348

41.2 Adding LiveData to the ViewModel....348

41.3 Implementing the Observer....350

41.4 Summary....351

42. An Overview of Android Jetpack Data Binding....352

42.1 An Overview of Data Binding....352

42.2 The Key Components of Data Binding....352

42.2.1 The Project Build Configuration....352

42.2.2 The Data Binding Layout File....353

42.2.3 The Layout File Data Element....354

42.2.4 The Binding Classes....355

42.2.5 Data Binding Variable Configuration....355

42.2.6 Binding Expressions (One-Way)....356

42.2.7 Binding Expressions (Two-Way)....357

42.2.8 Event and Listener Bindings....357

42.3 Summary....358

43. An Android Jetpack Data Binding Tutorial....360

43.1 Removing the Redundant Code....360

43.2 Enabling Data Binding....361

43.3 Adding the Layout Element....362

43.4 Adding the Data Element to Layout File....363

43.5 Working with the Binding Class....363

43.6 Assigning the ViewModel Instance to the Data Binding Variable....364

43.7 Adding Binding Expressions....365

43.8 Adding the Conversion Method....366

43.9 Adding a Listener Binding....366

43.10 Testing the App....367

43.11 Summary....367

44. An Android ViewModel Saved State Tutorial....368

44.1 Understanding ViewModel State Saving....368

44.2 Implementing ViewModel State Saving....368

44.3 Saving and Restoring State....369

44.4 Adding Saved State Support to the ViewModelDemo Project....370

44.5 Summary....371

45. Working with Android Lifecycle-Aware Components....372

45.1 Lifecycle Awareness....372

45.2 Lifecycle Owners....372

45.3 Lifecycle Observers....373

45.4 Lifecycle States and Events....373

45.5 Summary....374

46. An Android Jetpack Lifecycle Awareness Tutorial....376

46.1 Creating the Example Lifecycle Project....376

46.2 Creating a Lifecycle Observer....376

46.3 Adding the Observer....377

46.4 Testing the Observer....378

46.5 Creating a Lifecycle Owner....378

46.6 Testing the Custom Lifecycle Owner....380

46.7 Summary....380

47. An Overview of the Navigation Architecture Component....382

47.1 Understanding Navigation....382

47.2 Declaring a Navigation Host....383

47.3 The Navigation Graph....385

47.4 Accessing the Navigation Controller....386

47.5 Triggering a Navigation Action....386

47.6 Passing Arguments....387

47.7 Summary....387

48. An Android Jetpack Navigation Component Tutorial....388

48.1 Creating the NavigationDemo Project....388

48.2 Adding Navigation to the Build Configuration....388

48.3 Creating the Navigation Graph Resource File....389

48.4 Declaring a Navigation Host....390

48.5 Adding Navigation Destinations....391

48.6 Designing the Destination Fragment Layouts....393

48.7 Adding an Action to the Navigation Graph....394

48.8 Implement the OnFragmentInteractionListener....396

48.9 Adding View Binding Support to the Destination Fragments....397

48.10 Triggering the Action....397

48.11 Passing Data Using Safeargs....398

48.12 Summary....401

49. An Introduction to MotionLayout....402

49.1 An Overview of MotionLayout....402

49.2 MotionLayout....402

49.3 MotionScene....402

49.4 Configuring ConstraintSets....403

49.5 Custom Attributes....404

49.6 Triggering an Animation....406

49.7 Arc Motion....407

49.8 Keyframes....407

49.8.1 Attribute Keyframes....407

49.8.2 Position Keyframes....408

49.9 Time Linearity....411

49.10 KeyTrigger....411

49.11 Cycle and Time Cycle Keyframes....412

49.12 Starting an Animation from Code....412

49.13 Summary....413

50. An Android MotionLayout Editor Tutorial....414

50.1 Creating the MotionLayoutDemo Project....414

50.2 ConstraintLayout to MotionLayout Conversion....414

50.3 Configuring Start and End Constraints....416

50.4 Previewing the MotionLayout Animation....419

50.5 Adding an OnClick Gesture....419

50.6 Adding an Attribute Keyframe to the Transition....421

50.7 Adding a CustomAttribute to a Transition....423

50.8 Adding Position Keyframes....425

50.9 Summary....427

51. A MotionLayout KeyCycle Tutorial....428

51.1 An Overview of Cycle Keyframes....428

51.2 Using the Cycle Editor....432

51.3 Creating the KeyCycleDemo Project....433

51.4 Configuring the Start and End Constraints....433

51.5 Creating the Cycles....435

51.6 Previewing the Animation....437

51.7 Adding the KeyFrameSet to the MotionScene....437

51.8 Summary....439

52. Working with the Floating Action Button and Snackbar....440

52.1 The Material Design....440

52.2 The Design Library....440

52.3 The Floating Action Button (FAB) ....440

52.4 The Snackbar....441

52.5 Creating the Example Project....442

52.6 Reviewing the Project....442

52.7 Removing Navigation Features....443

52.8 Changing the Floating Action Button....443

52.9 Adding an Action to the Snackbar....445

52.10 Summary....445

53. Creating a Tabbed Interface using the TabLayout Component....446

53.1 An Introduction to the ViewPager2....446

53.2 An Overview of the TabLayout Component....446

53.3 Creating the TabLayoutDemo Project....447

53.4 Creating the First Fragment....447

53.5 Duplicating the Fragments....449

53.6 Adding the TabLayout and ViewPager2....450

53.7 Performing the Initialization Tasks....452

53.8 Testing the Application....454

53.9 Customizing the TabLayout....454

53.10 Summary....456

54. Working with the RecyclerView and CardView Widgets....458

54.1 An Overview of the RecyclerView....458

54.2 An Overview of the CardView....460

54.3 Summary....461

55. An Android RecyclerView and CardView Tutorial....462

55.1 Creating the CardDemo Project....462

55.2 Modifying the Basic Views Activity Project....462

55.3 Designing the CardView Layout....463

55.4 Adding the RecyclerView....464

55.5 Adding the Image Files....464

55.6 Creating the RecyclerView Adapter....464

55.7 Initializing the RecyclerView Component....466

55.8 Testing the Application....467

55.9 Responding to Card Selections....468

55.10 Summary....470

56. Working with the AppBar and Collapsing Toolbar Layouts....472

56.1 The Anatomy of an AppBar....472

56.2 The Example Project....473

56.3 Coordinating the RecyclerView and Toolbar....473

56.4 Introducing the Collapsing Toolbar Layout....475

56.5 Changing the Title and Scrim Color....478

56.6 Summary....479

57. An Overview of Android Intents....480

57.1 An Overview of Intents....480

57.2 Explicit Intents....480

57.3 Returning Data from an Activity....481

57.4 Implicit Intents....482

57.5 Using Intent Filters....483

57.6 Automatic Link Verification....483

57.7 Manually Enabling Links....486

57.8 Checking Intent Availability....487

57.9 Summary....488

58. Android Explicit Intents – A Worked Example....490

58.1 Creating the Explicit Intent Example Application....490

58.2 Designing the User Interface Layout for MainActivity....490

58.3 Creating the Second Activity Class....491

58.4 Designing the User Interface Layout for SecondActivity....492

58.5 Reviewing the Application Manifest File....492

58.6 Creating the Intent....493

58.7 Extracting Intent Data....494

58.8 Launching SecondActivity as a Sub-Activity....495

58.9 Returning Data from a Sub-Activity....496

58.10 Testing the Application....496

58.11 Summary....496

59. Android Implicit Intents – A Worked Example....498

59.1 Creating the Android Studio Implicit Intent Example Project....498

59.2 Designing the User Interface....498

59.3 Creating the Implicit Intent....499

59.4 Adding a Second Matching Activity....500

59.5 Adding the Web View to the UI....500

59.6 Obtaining the Intent URL....501

59.7 Modifying the MyWebView Project Manifest File....502

59.8 Installing the MyWebView Package on a Device....503

59.9 Testing the Application....504

59.10 Manually Enabling the Link....504

59.11 Automatic Link Verification....506

59.12 Summary....508

60. Android Broadcast Intents and Broadcast Receivers....510

60.1 An Overview of Broadcast Intents....510

60.2 An Overview of Broadcast Receivers....511

60.3 Obtaining Results from a Broadcast....512

60.4 Sticky Broadcast Intents....512

60.5 The Broadcast Intent Example....512

60.6 Creating the Example Application....513

60.7 Creating and Sending the Broadcast Intent....513

60.8 Creating the Broadcast Receiver....514

60.9 Registering the Broadcast Receiver....515

60.10 Testing the Broadcast Example....516

60.11 Listening for System Broadcasts....516

60.12 Summary....516

61. An Introduction to Kotlin Coroutines....518

61.1 What are Coroutines?....518

61.2 Threads vs. Coroutines....518

61.3 Coroutine Scope....519

61.4 Suspend Functions....519

61.5 Coroutine Dispatchers....519

61.6 Coroutine Builders....520

61.7 Jobs....520

61.8 Coroutines – Suspending and Resuming....521

61.9 Returning Results from a Coroutine....522

61.10 Using withContext....522

61.11 Coroutine Channel Communication....524

61.12 Summary....525

62. An Android Kotlin Coroutines Tutorial....526

62.1 Creating the Coroutine Example Application....526

62.2 Adding Coroutine Support to the Project....526

62.3 Designing the User Interface....526

62.4 Implementing the SeekBar....528

62.5 Adding the Suspend Function....528

62.6 Implementing the launchCoroutines Method....529

62.7 Testing the App....530

62.8 Summary....530

63. An Overview of Android Services....532

63.1 Intent Service....532

63.2 Bound Service....532

63.3 The Anatomy of a Service....533

63.4 Controlling Destroyed Service Restart Options....533

63.5 Declaring a Service in the Manifest File....533

63.6 Starting a Service Running on System Startup....534

63.7 Summary....535

64. Android Local Bound Services – A Worked Example....536

64.1 Understanding Bound Services....536

64.2 Bound Service Interaction Options....536

64.3 A Local Bound Service Example....536

64.4 Adding a Bound Service to the Project....537

64.5 Implementing the Binder....537

64.6 Binding the Client to the Service....539

64.7 Completing the Example....540

64.8 Testing the Application....541

64.9 Summary....542

65. Android Remote Bound Services – A Worked Example....544

65.1 Client to Remote Service Communication....544

65.2 Creating the Example Application....544

65.3 Designing the User Interface....544

65.4 Implementing the Remote Bound Service....544

65.5 Configuring a Remote Service in the Manifest File....546

65.6 Launching and Binding to the Remote Service....546

65.7 Sending a Message to the Remote Service....548

65.8 Summary....548

66. An Introduction to Kotlin Flow....550

66.1 Understanding Flows....550

66.2 Creating the Sample Project....550

66.3 Adding the Kotlin Lifecycle Library....551

66.4 Declaring a Flow....551

66.5 Emitting Flow Data....552

66.6 Collecting Flow Data....552

66.7 Adding a Flow Buffer....553

66.8 Transforming Data with Intermediaries....555

66.9 Terminal Flow Operators....556

66.10 Flow Flattening....557

66.11 Combining Multiple Flows....558

66.12 Hot and Cold Flows....559

66.13 StateFlow....560

66.14 SharedFlow....561

66.15 Summary....562

67. An Android SharedFlow Tutorial....564

67.1 About the Project....564

67.2 Creating the SharedFlowDemo Project....564

67.3 Designing the User Interface Layout....564

67.4 Adding the List Row Layout....564

67.5 Adding the RecyclerView Adapter....565

67.6 Adding the ViewModel....566

67.7 Configuring the ViewModelProvider....567

67.8 Collecting the Flow Values....568

67.9 Testing the SharedFlowDemo App....569

67.10 Handling Flows in the Background....569

67.11 Summary....572

68. An Overview of Android SQLite Databases....574

68.1 Understanding Database Tables....574

68.2 Introducing Database Schema ....574

68.3 Columns and Data Types ....574

68.4 Database Rows ....575

68.5 Introducing Primary Keys ....575

68.6 What is SQLite?....575

68.7 Structured Query Language (SQL)....575

68.8 Trying SQLite on an Android Virtual Device (AVD)....576

68.9 The Android Room Persistence Library....577

68.10 Summary....578

69. The Android Room Persistence Library....580

69.1 Revisiting Modern App Architecture....580

69.2 Key Elements of Room Database Persistence....580

69.2.1 Repository....581

69.2.2 Room Database....581

69.2.3 Data Access Object (DAO)....581

69.2.4 Entities....581

69.2.5 SQLite Database....581

69.3 Understanding Entities....582

69.4 Data Access Objects....584

69.5 The Room Database....585

69.6 The Repository....586

69.7 In-Memory Databases....587

69.8 Database Inspector....587

69.9 Summary....588

70. An Android TableLayout and TableRow Tutorial....590

70.1 The TableLayout and TableRow Layout Views....590

70.2 Creating the Room Database Project....591

70.3 Converting to a LinearLayout....591

70.4 Adding the TableLayout to the User Interface....592

70.5 Configuring the TableRows....593

70.6 Adding the Button Bar to the Layout....594

70.7 Adding the RecyclerView....595

70.8 Adjusting the Layout Margins....596

70.9 Summary....596

71. An Android Room Database and Repository Tutorial....598

71.1 About the RoomDemo Project....598

71.2 Modifying the Build Configuration....598

71.3 Building the Entity....599

71.4 Creating the Data Access Object....600

71.5 Adding the Room Database....602

71.6 Adding the Repository....602

71.7 Adding the ViewModel....605

71.8 Creating the Product Item Layout....606

71.9 Adding the RecyclerView Adapter....607

71.10 Preparing the Main Activity....608

71.11 Adding the Button Listeners....609

71.12 Adding LiveData Observers....610

71.13 Initializing the RecyclerView....610

71.14 Testing the RoomDemo App....611

71.15 Using the Database Inspector....611

71.16 Summary....612

72. Video Playback on Android using the VideoView and MediaController Classes....614

72.1 Introducing the Android VideoView Class....614

72.2 Introducing the Android MediaController Class....615

72.3 Creating the Video Playback Example....615

72.4 Designing the VideoPlayer Layout....615

72.5 Downloading the Video File....616

72.6 Configuring the VideoView....616

72.7 Adding the MediaController to the Video View....618

72.8 Setting up the onPreparedListener....618

72.9 Summary....619

73. Android Picture-in-Picture Mode....620

73.1 Picture-in-Picture Features....620

73.2 Enabling Picture-in-Picture Mode....621

73.3 Configuring Picture-in-Picture Parameters....621

73.4 Entering Picture-in-Picture Mode....622

73.5 Detecting Picture-in-Picture Mode Changes....622

73.6 Adding Picture-in-Picture Actions....622

73.7 Summary....623

74. An Android Picture-in-Picture Tutorial....624

74.1 Adding Picture-in-Picture Support to the Manifest....624

74.2 Adding a Picture-in-Picture Button....624

74.3 Entering Picture-in-Picture Mode....625

74.4 Detecting Picture-in-Picture Mode Changes....626

74.5 Adding a Broadcast Receiver....626

74.6 Adding the PiP Action....627

74.7 Testing the Picture-in-Picture Action....630

74.8 Summary....630

75. Making Runtime Permission Requests in Android....632

75.1 Understanding Normal and Dangerous Permissions....632

75.2 Creating the Permissions Example Project....634

75.3 Checking for a Permission....634

75.4 Requesting Permission at Runtime....636

75.5 Providing a Rationale for the Permission Request....637

75.6 Testing the Permissions App....638

75.7 Summary....639

76. Android Audio Recording and Playback using MediaPlayer and MediaRecorder....640

76.1 Playing Audio....640

76.2 Recording Audio and Video using the MediaRecorder Class....641

76.3 About the Example Project....642

76.4 Creating the AudioApp Project....642

76.5 Designing the User Interface....642

76.6 Checking for Microphone Availability....643

76.7 Initializing the Activity....644

76.8 Implementing the recordAudio() Method....645

76.9 Implementing the stopAudio() Method....645

76.10 Implementing the playAudio() method....646

76.11 Configuring and Requesting Permissions....646

76.12 Testing the Application....648

76.13 Summary....648

77. An Android Notifications Tutorial....650

77.1 An Overview of Notifications....650

77.2 Creating the NotifyDemo Project....652

77.3 Designing the User Interface....652

77.4 Creating the Second Activity....652

77.5 Creating a Notification Channel....653

77.6 Requesting Notification Permission....654

77.7 Creating and Issuing a Notification....657

77.8 Launching an Activity from a Notification....659

77.9 Adding Actions to a Notification....661

77.10 Bundled Notifications....661

77.11 Summary....663

78. An Android Direct Reply Notification Tutorial....664

78.1 Creating the DirectReply Project....664

78.2 Designing the User Interface....664

78.3 Requesting Notification Permission....665

78.4 Creating the Notification Channel....666

78.5 Building the RemoteInput Object....667

78.6 Creating the PendingIntent....668

78.7 Creating the Reply Action....669

78.8 Receiving Direct Reply Input....670

78.9 Updating the Notification....671

78.10 Summary....672

79. Working with the Google Maps Android API in Android Studio....674

79.1 The Elements of the Google Maps Android API....674

79.2 Creating the Google Maps Project....675

79.3 Creating a Google Cloud Billing Account....675

79.4 Creating a New Google Cloud Project....676

79.5 Enabling the Google Maps SDK....677

79.6 Generating a Google Maps API Key....678

79.7 Adding the API Key to the Android Studio Project....679

79.8 Testing the Application....679

79.9 Understanding Geocoding and Reverse Geocoding....679

79.10 Adding a Map to an Application....681

79.11 Requesting Current Location Permission....681

79.12 Displaying the Users Current Location....683

79.13 Changing the Map Type....684

79.14 Displaying Map Controls to the User....685

79.15 Handling Map Gesture Interaction....685

79.15.1 Map Zooming Gestures....685

79.15.2 Map ScrollingPanning Gestures....686

79.15.3 Map Tilt Gestures....686

79.15.4 Map Rotation Gestures....686

79.16 Creating Map Markers....686

79.17 Controlling the Map Camera....687

79.18 Summary....688

80. Printing with the Android Printing Framework....690

80.1 The Android Printing Architecture....690

80.2 The Print Service Plugins....690

80.3 Google Cloud Print....691

80.4 Printing to Google Drive....691

80.5 Save as PDF....692

80.6 Printing from Android Devices....692

80.7 Options for Building Print Support into Android Apps....693

80.7.1 Image Printing....693

80.7.2 Creating and Printing HTML Content....694

80.7.3 Printing a Web Page....695

80.7.4 Printing a Custom Document....696

80.8 Summary....696

81. An Android HTML and Web Content Printing Example....698

81.1 Creating the HTML Printing Example Application....698

81.2 Printing Dynamic HTML Content....698

81.3 Creating the Web Page Printing Example....701

81.4 Removing the Floating Action Button....701

81.5 Removing Navigation Features....701

81.6 Designing the User Interface Layout....702

81.7 Accessing the WebView from the Main Activity....703

81.8 Loading the Web Page into the WebView....703

81.9 Adding the Print Menu Option....704

81.10 Summary....706

82. A Guide to Android Custom Document Printing....708

82.1 An Overview of Android Custom Document Printing....708

82.1.1 Custom Print Adapters....708

82.2 Preparing the Custom Document Printing Project....709

82.3 Creating the Custom Print Adapter....710

82.4 Implementing the onLayout() Callback Method....711

82.5 Implementing the onWrite() Callback Method....714

82.6 Checking a Page is in Range....716

82.7 Drawing the Content on the Page Canvas....717

82.8 Starting the Print Job....719

82.9 Testing the Application....720

82.10 Summary....720

83. An Introduction to Android App Links....722

83.1 An Overview of Android App Links....722

83.2 App Link Intent Filters....722

83.3 Handling App Link Intents....723

83.4 Associating the App with a Website....723

83.5 Summary....724

84. An Android Studio App Links Tutorial....726

84.1 About the Example App....726

84.2 The Database Schema....726

84.3 Loading and Running the Project....726

84.4 Adding the URL Mapping....728

84.5 Adding the Intent Filter....731

84.6 Adding Intent Handling Code....731

84.7 Testing the App....734

84.8 Creating the Digital Asset Links File....734

84.9 Testing the App Link....735

84.10 Summary....735

85. An Android Biometric Authentication Tutorial....736

85.1 An Overview of Biometric Authentication....736

85.2 Creating the Biometric Authentication Project....736

85.3 Configuring Device Fingerprint Authentication....737

85.4 Adding the Biometric Permission to the Manifest File....737

85.5 Designing the User Interface....738

85.6 Adding a Toast Convenience Method....738

85.7 Checking the Security Settings....739

85.8 Configuring the Authentication Callbacks....740

85.9 Adding the CancellationSignal....741

85.10 Starting the Biometric Prompt....741

85.11 Testing the Project....742

85.12 Summary....743

86. Creating, Testing, and Uploading an Android App Bundle....744

86.1 The Release Preparation Process....744

86.2 Android App Bundles....744

86.3 Register for a Google Play Developer Console Account....745

86.4 Configuring the App in the Console....746

86.5 Enabling Google Play App Signing....747

86.6 Creating a Keystore File....747

86.7 Creating the Android App Bundle....748

86.8 Generating Test APK Files....750

86.9 Uploading the App Bundle to the Google Play Developer Console....751

86.10 Exploring the App Bundle....752

86.11 Managing Testers....753

86.12 Rolling the App Out for Testing....753

86.13 Uploading New App Bundle Revisions....754

86.14 Analyzing the App Bundle File....755

86.15 Summary....756

87. An Overview of Android In-App Billing....758

87.1 Preparing a Project for In-App Purchasing....758

87.2 Creating In-App Products and Subscriptions....758

87.3 Billing Client Initialization....759

87.4 Connecting to the Google Play Billing Library....760

87.5 Querying Available Products....760

87.6 Starting the Purchase Process....761

87.7 Completing the Purchase....761

87.8 Querying Previous Purchases....762

87.9 Summary....763

88. An Android In-App Purchasing Tutorial....764

88.1 About the In-App Purchasing Example Project....764

88.2 Creating the InAppPurchase Project....764

88.3 Adding Libraries to the Project....764

88.4 Designing the User Interface....765

88.5 Adding the App to the Google Play Store....765

88.6 Creating an In-App Product....766

88.7 Enabling License Testers....766

88.8 Initializing the Billing Client....767

88.9 Querying the Product....769

88.10 Launching the Purchase Flow....770

88.11 Handling Purchase Updates....770

88.12 Consuming the Product....771

88.13 Restoring a Previous Purchase....772

88.14 Testing the App....773

88.15 Troubleshooting....774

88.16 Summary....775

89. Working with Material Design 3 Theming....776

89.1 Material Design 2 vs. Material Design 3....776

89.2 Understanding Material Design Theming....776

89.3 Material Design 3 Theming....776

89.4 Building a Custom Theme....778

89.5 Summary....779

90. A Material Design 3 Theming and Dynamic Color Tutorial....780

90.1 Creating the ThemeDemo Project....780

90.2 Designing the User Interface....780

90.3 Building a New Theme....782

90.4 Adding the Theme to the Project....783

90.5 Enabling Dynamic Color Support....784

90.6 Previewing Dynamic Colors....785

90.7 Summary....786

91. An Overview of Gradle in Android Studio....788

91.1 An Overview of Gradle....788

91.2 Gradle and Android Studio....788

91.2.1 Sensible Defaults....788

91.2.2 Dependencies....788

91.2.3 Build Variants....789

91.2.4 Manifest Entries....789

91.2.5 APK Signing....789

91.2.6 ProGuard Support....789

91.3 The Property and Settings Gradle Build File....789

91.4 The Top-level Gradle Build File....790

91.5 Module Level Gradle Build Files....791

91.6 Configuring Signing Settings in the Build File....793

91.7 Running Gradle Tasks from the Command Line....794

91.8 Summary....795

Index....796

Fully updated for Android Studio Giraffe and the new UI, this book teaches you how to develop Android-based applications using the Kotlin programming language.

This book begins with the basics and outlines how to set up an Android development and testing environment, followed by an introduction to programming in Kotlin, including data types, control flow, functions, lambdas, and object-oriented programming. Asynchronous programming using Kotlin coroutines and flow is also covered in detail.

Chapters also cover the Android Architecture Components, including view models, lifecycle management, Room database access, the Database Inspector, app navigation, live data, and data binding.

More advanced topics such as intents are also covered, as are touch screen handling, gesture recognition, and the recording and playback of audio. This book edition also covers printing, transitions, and foldable device support.

The concepts of material design are also covered in detail, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars.

Other key features of Android Studio and Android are also covered in detail, including the Layout Editor, the ConstraintLayout and ConstraintSet classes, MotionLayout Editor, view binding, constraint chains, barriers, and direct reply notifications.

Chapters also cover advanced features of Android Studio, such as App Links, Gradle build configuration, in-app billing, and submitting apps to the Google Play Developer Console.

Assuming you already have some programming experience, are ready to download Android Studio and the Android SDK, have access to a Windows, Mac, or Linux system, and have ideas for some apps to develop, you are ready to get started.